As a printer for cans, there has been known one which includes a can supply means for supplying cans, plural ink supply means for supplying ink for respective colors, plural plate cylinders provided so as to correspond to respective ink supply means, to which ink supplied from the ink supply means is applied and a blanket transferring ink to cans supplied from the can supply means after the ink is sequentially transferred from respective plate cylinders (Patent Literature 1).
There is also disclosed in Patent Literature 2 an inspection device performing inspections of print states of cans which includes a rotation device rotating cans, an imaging device taking images of rotating cans and an image processor processing the taken images.
In Patent Literature 2, the image processor has an image inspection means for inspecting whether printing is performed properly as compared with a master image, in which a lack of printing, a stain in appearance and so on are inspected by the image inspection means.